If you can trust the parameter being passed in, then yes. That means trust the format and trust the content (i.e could it ever be YYYY-DD-MM, YYYY-Mon-DD or refer to 30th February etc.)

You might try:-

Code:

#!/bin/ksh
input_param=$1
YYYY="${input_param%%-*}"
MM="${input_param#*-}" ; MM="${MM%-*}"
DD="${input_param##*-}"
echo "The year is $YYYY"
echo "The month is $MM"
echo "The day is $DD"

This way of splitting up the string is called variable substitution. You can then touch a file for the start of the month and one for the end of 'today' from which you can then use find to list the files in between.

How far have you got? It would be better for you if we can help you build something you can support and adjust rather than just giving a working solution.